This invention relates generally to a magnetic resonance imaging system (hereinafter referred to as "MRI system"), and more particularly to a MRI system in which considerations, contributing to easy handling, are given to the subject to be examined (hereinafter referred to as "patient"), and also the efficiency of operations, such as a medical treatment to be given to the patient by a doctor, and an examination operation to be effected by a technician or the like (The doctor and the technician will hereinafter be referred to as "doctor or the like"), is improved.
A MRI system utilizes nuclear magnetic resonance (NMR) phenomena to provide an image of a cross-sectional area of that portion of the patient to be examined for diagnostic purposes. In such a MRI system, in order to produce NMR phenomena on the patient's portion to be examined, it is necessary to produce a strong magnetic field and then to locate the patient's portion to be examined in this magnetic field.
In conventional MRI systems, generally, a bore such as a tunnel is formed in a strong magnetic field, and the patient is put into this bore. In such a system, although the strong magnetic field can be easily formed, the patient must be loaded into the narrow bore, which has invited a problem that the examination can not be carried out easily. Japanese Patent Unexamined Publication No. 62-26052 discloses a MRI system not using a tunnel space, in which one side of a measurement space is open.
In the conventional MRI systems, the measurement space is formed in the tunnel, or is open at its one side with the remaining sides closed by walls. Therefore, when the patient is inserted into the measurement space for examination purposes, he tends to feel oppressed and uneasy, and it has often been difficult to properly examine a patient having claustrophobia. Moreover, the doctors or the like have now increasingly desired to give a medical treatment to the patient simultaneously with the examination operation; particulerly when the patient has an emergency condition, it is necessary to effect a medical treatment simultaneously with the examination. In such a case, the doctors or the like need to gain access to the patient from opposite sides of the patient. With conventional MRI systems, however, it has been impossible to achieve this.